xref: /linux/include/linux/f2fs_fs.h (revision 60684c2bd35064043360e6f716d1b7c20e967b7d)
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * include/linux/f2fs_fs.h
4  *
5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6  *             http://www.samsung.com/
7  */
8 #ifndef _LINUX_F2FS_FS_H
9 #define _LINUX_F2FS_FS_H
10 
11 #include <linux/pagemap.h>
12 #include <linux/types.h>
13 
14 #define F2FS_SUPER_OFFSET		1024	/* byte-size offset */
15 #define F2FS_MIN_LOG_SECTOR_SIZE	9	/* 9 bits for 512 bytes */
16 #define F2FS_MAX_LOG_SECTOR_SIZE	12	/* 12 bits for 4096 bytes */
17 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* log number for sector/blk */
18 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
19 #define F2FS_BLKSIZE_BITS		12	/* bits for F2FS_BLKSIZE */
20 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
21 #define F2FS_EXTENSION_LEN		8	/* max size of extension */
22 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) >> F2FS_BLKSIZE_BITS)
23 
24 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
25 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
26 #define COMPRESS_ADDR		((block_t)-2)	/* used as compressed data flag */
27 
28 #define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
29 #define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
30 
31 /* 0, 1(node nid), 2(meta nid) are reserved node id */
32 #define F2FS_RESERVED_NODE_NUM		3
33 
34 #define F2FS_ROOT_INO(sbi)	((sbi)->root_ino_num)
35 #define F2FS_NODE_INO(sbi)	((sbi)->node_ino_num)
36 #define F2FS_META_INO(sbi)	((sbi)->meta_ino_num)
37 #define F2FS_COMPRESS_INO(sbi)	(NM_I(sbi)->max_nid)
38 
39 #define F2FS_MAX_QUOTAS		3
40 
41 #define F2FS_ENC_UTF8_12_1	1
42 
43 #define F2FS_IO_SIZE(sbi)	(1 << F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
44 #define F2FS_IO_SIZE_KB(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 2)) /* KB */
45 #define F2FS_IO_SIZE_BYTES(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 12)) /* B */
46 #define F2FS_IO_SIZE_BITS(sbi)	(F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
47 #define F2FS_IO_SIZE_MASK(sbi)	(F2FS_IO_SIZE(sbi) - 1)
48 #define F2FS_IO_ALIGNED(sbi)	(F2FS_IO_SIZE(sbi) > 1)
49 
50 /* This flag is used by node and meta inodes, and by recovery */
51 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
52 
53 /*
54  * For further optimization on multi-head logs, on-disk layout supports maximum
55  * 16 logs by default. The number, 16, is expected to cover all the cases
56  * enoughly. The implementaion currently uses no more than 6 logs.
57  * Half the logs are used for nodes, and the other half are used for data.
58  */
59 #define MAX_ACTIVE_LOGS	16
60 #define MAX_ACTIVE_NODE_LOGS	8
61 #define MAX_ACTIVE_DATA_LOGS	8
62 
63 #define VERSION_LEN	256
64 #define MAX_VOLUME_NAME		512
65 #define MAX_PATH_LEN		64
66 #define MAX_DEVICES		8
67 
68 /*
69  * For superblock
70  */
71 struct f2fs_device {
72 	__u8 path[MAX_PATH_LEN];
73 	__le32 total_segments;
74 } __packed;
75 
76 /* reason of stop_checkpoint */
77 enum stop_cp_reason {
78 	STOP_CP_REASON_SHUTDOWN,
79 	STOP_CP_REASON_FAULT_INJECT,
80 	STOP_CP_REASON_META_PAGE,
81 	STOP_CP_REASON_WRITE_FAIL,
82 	STOP_CP_REASON_CORRUPTED_SUMMARY,
83 	STOP_CP_REASON_UPDATE_INODE,
84 	STOP_CP_REASON_FLUSH_FAIL,
85 	STOP_CP_REASON_MAX,
86 };
87 
88 #define	MAX_STOP_REASON			32
89 
90 /* detail reason for EFSCORRUPTED */
91 enum f2fs_error {
92 	ERROR_CORRUPTED_CLUSTER,
93 	ERROR_FAIL_DECOMPRESSION,
94 	ERROR_INVALID_BLKADDR,
95 	ERROR_CORRUPTED_DIRENT,
96 	ERROR_CORRUPTED_INODE,
97 	ERROR_INCONSISTENT_SUMMARY,
98 	ERROR_INCONSISTENT_FOOTER,
99 	ERROR_INCONSISTENT_SUM_TYPE,
100 	ERROR_CORRUPTED_JOURNAL,
101 	ERROR_INCONSISTENT_NODE_COUNT,
102 	ERROR_INCONSISTENT_BLOCK_COUNT,
103 	ERROR_INVALID_CURSEG,
104 	ERROR_INCONSISTENT_SIT,
105 	ERROR_CORRUPTED_VERITY_XATTR,
106 	ERROR_CORRUPTED_XATTR,
107 	ERROR_MAX,
108 };
109 
110 #define MAX_F2FS_ERRORS			16
111 
112 struct f2fs_super_block {
113 	__le32 magic;			/* Magic Number */
114 	__le16 major_ver;		/* Major Version */
115 	__le16 minor_ver;		/* Minor Version */
116 	__le32 log_sectorsize;		/* log2 sector size in bytes */
117 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
118 	__le32 log_blocksize;		/* log2 block size in bytes */
119 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
120 	__le32 segs_per_sec;		/* # of segments per section */
121 	__le32 secs_per_zone;		/* # of sections per zone */
122 	__le32 checksum_offset;		/* checksum offset inside super block */
123 	__le64 block_count;		/* total # of user blocks */
124 	__le32 section_count;		/* total # of sections */
125 	__le32 segment_count;		/* total # of segments */
126 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
127 	__le32 segment_count_sit;	/* # of segments for SIT */
128 	__le32 segment_count_nat;	/* # of segments for NAT */
129 	__le32 segment_count_ssa;	/* # of segments for SSA */
130 	__le32 segment_count_main;	/* # of segments for main area */
131 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
132 	__le32 cp_blkaddr;		/* start block address of checkpoint */
133 	__le32 sit_blkaddr;		/* start block address of SIT */
134 	__le32 nat_blkaddr;		/* start block address of NAT */
135 	__le32 ssa_blkaddr;		/* start block address of SSA */
136 	__le32 main_blkaddr;		/* start block address of main area */
137 	__le32 root_ino;		/* root inode number */
138 	__le32 node_ino;		/* node inode number */
139 	__le32 meta_ino;		/* meta inode number */
140 	__u8 uuid[16];			/* 128-bit uuid for volume */
141 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
142 	__le32 extension_count;		/* # of extensions below */
143 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
144 	__le32 cp_payload;
145 	__u8 version[VERSION_LEN];	/* the kernel version */
146 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
147 	__le32 feature;			/* defined features */
148 	__u8 encryption_level;		/* versioning level for encryption */
149 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
150 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
151 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
152 	__u8 hot_ext_count;		/* # of hot file extension */
153 	__le16  s_encoding;		/* Filename charset encoding */
154 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
155 	__u8 s_stop_reason[MAX_STOP_REASON];	/* stop checkpoint reason */
156 	__u8 s_errors[MAX_F2FS_ERRORS];		/* reason of image corrupts */
157 	__u8 reserved[258];		/* valid reserved region */
158 	__le32 crc;			/* checksum of superblock */
159 } __packed;
160 
161 /*
162  * For checkpoint
163  */
164 #define CP_RESIZEFS_FLAG		0x00004000
165 #define CP_DISABLED_QUICK_FLAG		0x00002000
166 #define CP_DISABLED_FLAG		0x00001000
167 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
168 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
169 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
170 #define CP_TRIMMED_FLAG		0x00000100
171 #define CP_NAT_BITS_FLAG	0x00000080
172 #define CP_CRC_RECOVERY_FLAG	0x00000040
173 #define CP_FASTBOOT_FLAG	0x00000020
174 #define CP_FSCK_FLAG		0x00000010
175 #define CP_ERROR_FLAG		0x00000008
176 #define CP_COMPACT_SUM_FLAG	0x00000004
177 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
178 #define CP_UMOUNT_FLAG		0x00000001
179 
180 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
181 
182 struct f2fs_checkpoint {
183 	__le64 checkpoint_ver;		/* checkpoint block version number */
184 	__le64 user_block_count;	/* # of user blocks */
185 	__le64 valid_block_count;	/* # of valid blocks in main area */
186 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
187 	__le32 overprov_segment_count;	/* # of overprovision segments */
188 	__le32 free_segment_count;	/* # of free segments in main area */
189 
190 	/* information of current node segments */
191 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
192 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
193 	/* information of current data segments */
194 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
195 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
196 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
197 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
198 	__le32 cp_pack_start_sum;	/* start block number of data summary */
199 	__le32 valid_node_count;	/* Total number of valid nodes */
200 	__le32 valid_inode_count;	/* Total number of valid inodes */
201 	__le32 next_free_nid;		/* Next free node number */
202 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
203 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
204 	__le32 checksum_offset;		/* checksum offset inside cp block */
205 	__le64 elapsed_time;		/* mounted time */
206 	/* allocation type of current segment */
207 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
208 
209 	/* SIT and NAT version bitmap */
210 	unsigned char sit_nat_version_bitmap[];
211 } __packed;
212 
213 #define CP_CHKSUM_OFFSET	4092	/* default chksum offset in checkpoint */
214 #define CP_MIN_CHKSUM_OFFSET						\
215 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
216 
217 /*
218  * For orphan inode management
219  */
220 #define F2FS_ORPHANS_PER_BLOCK	1020
221 
222 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
223 					F2FS_ORPHANS_PER_BLOCK)
224 
225 struct f2fs_orphan_block {
226 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
227 	__le32 reserved;	/* reserved */
228 	__le16 blk_addr;	/* block index in current CP */
229 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
230 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
231 	__le32 check_sum;	/* CRC32 for orphan inode block */
232 } __packed;
233 
234 /*
235  * For NODE structure
236  */
237 struct f2fs_extent {
238 	__le32 fofs;		/* start file offset of the extent */
239 	__le32 blk;		/* start block address of the extent */
240 	__le32 len;		/* length of the extent */
241 } __packed;
242 
243 #define F2FS_NAME_LEN		255
244 /* 200 bytes for inline xattrs by default */
245 #define DEFAULT_INLINE_XATTR_ADDRS	50
246 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
247 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
248 					get_extra_isize(inode))
249 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
250 #define ADDRS_PER_INODE(inode)	addrs_per_inode(inode)
251 #define DEF_ADDRS_PER_BLOCK	1018	/* Address Pointers in a Direct Block */
252 #define ADDRS_PER_BLOCK(inode)	addrs_per_block(inode)
253 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
254 
255 #define ADDRS_PER_PAGE(page, inode)	\
256 	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
257 
258 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
259 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
260 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
261 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
262 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
263 
264 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
265 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
266 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
267 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
268 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
269 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
270 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
271 #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
272 
273 struct f2fs_inode {
274 	__le16 i_mode;			/* file mode */
275 	__u8 i_advise;			/* file hints */
276 	__u8 i_inline;			/* file inline flags */
277 	__le32 i_uid;			/* user ID */
278 	__le32 i_gid;			/* group ID */
279 	__le32 i_links;			/* links count */
280 	__le64 i_size;			/* file size in bytes */
281 	__le64 i_blocks;		/* file size in blocks */
282 	__le64 i_atime;			/* access time */
283 	__le64 i_ctime;			/* change time */
284 	__le64 i_mtime;			/* modification time */
285 	__le32 i_atime_nsec;		/* access time in nano scale */
286 	__le32 i_ctime_nsec;		/* change time in nano scale */
287 	__le32 i_mtime_nsec;		/* modification time in nano scale */
288 	__le32 i_generation;		/* file version (for NFS) */
289 	union {
290 		__le32 i_current_depth;	/* only for directory depth */
291 		__le16 i_gc_failures;	/*
292 					 * # of gc failures on pinned file.
293 					 * only for regular files.
294 					 */
295 	};
296 	__le32 i_xattr_nid;		/* nid to save xattr */
297 	__le32 i_flags;			/* file attributes */
298 	__le32 i_pino;			/* parent inode number */
299 	__le32 i_namelen;		/* file name length */
300 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
301 	__u8 i_dir_level;		/* dentry_level for large dir */
302 
303 	struct f2fs_extent i_ext;	/* caching a largest extent */
304 
305 	union {
306 		struct {
307 			__le16 i_extra_isize;	/* extra inode attribute size */
308 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
309 			__le32 i_projid;	/* project id */
310 			__le32 i_inode_checksum;/* inode meta checksum */
311 			__le64 i_crtime;	/* creation time */
312 			__le32 i_crtime_nsec;	/* creation time in nano scale */
313 			__le64 i_compr_blocks;	/* # of compressed blocks */
314 			__u8 i_compress_algorithm;	/* compress algorithm */
315 			__u8 i_log_cluster_size;	/* log of cluster size */
316 			__le16 i_compress_flag;		/* compress flag */
317 						/* 0 bit: chksum flag
318 						 * [8,15] bits: compress level
319 						 */
320 			__le32 i_extra_end[0];	/* for attribute size calculation */
321 		} __packed;
322 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
323 	};
324 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
325 						double_indirect(1) node id */
326 } __packed;
327 
328 struct direct_node {
329 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
330 } __packed;
331 
332 struct indirect_node {
333 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
334 } __packed;
335 
336 enum {
337 	COLD_BIT_SHIFT = 0,
338 	FSYNC_BIT_SHIFT,
339 	DENT_BIT_SHIFT,
340 	OFFSET_BIT_SHIFT
341 };
342 
343 #define OFFSET_BIT_MASK		(0x07)	/* (0x01 << OFFSET_BIT_SHIFT) - 1 */
344 
345 struct node_footer {
346 	__le32 nid;		/* node id */
347 	__le32 ino;		/* inode number */
348 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
349 	__le64 cp_ver;		/* checkpoint version */
350 	__le32 next_blkaddr;	/* next node page block address */
351 } __packed;
352 
353 struct f2fs_node {
354 	/* can be one of three types: inode, direct, and indirect types */
355 	union {
356 		struct f2fs_inode i;
357 		struct direct_node dn;
358 		struct indirect_node in;
359 	};
360 	struct node_footer footer;
361 } __packed;
362 
363 /*
364  * For NAT entries
365  */
366 #define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
367 
368 struct f2fs_nat_entry {
369 	__u8 version;		/* latest version of cached nat entry */
370 	__le32 ino;		/* inode number */
371 	__le32 block_addr;	/* block address */
372 } __packed;
373 
374 struct f2fs_nat_block {
375 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
376 } __packed;
377 
378 /*
379  * For SIT entries
380  *
381  * Each segment is 2MB in size by default so that a bitmap for validity of
382  * there-in blocks should occupy 64 bytes, 512 bits.
383  * Not allow to change this.
384  */
385 #define SIT_VBLOCK_MAP_SIZE 64
386 #define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
387 
388 /*
389  * F2FS uses 4 bytes to represent block address. As a result, supported size of
390  * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
391  */
392 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
393 
394 /*
395  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
396  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
397  * [9:0] : valid block count
398  */
399 #define SIT_VBLOCKS_SHIFT	10
400 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
401 #define GET_SIT_VBLOCKS(raw_sit)				\
402 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
403 #define GET_SIT_TYPE(raw_sit)					\
404 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
405 	 >> SIT_VBLOCKS_SHIFT)
406 
407 struct f2fs_sit_entry {
408 	__le16 vblocks;				/* reference above */
409 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
410 	__le64 mtime;				/* segment age for cleaning */
411 } __packed;
412 
413 struct f2fs_sit_block {
414 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
415 } __packed;
416 
417 /*
418  * For segment summary
419  *
420  * One summary block contains exactly 512 summary entries, which represents
421  * exactly 2MB segment by default. Not allow to change the basic units.
422  *
423  * NOTE: For initializing fields, you must use set_summary
424  *
425  * - If data page, nid represents dnode's nid
426  * - If node page, nid represents the node page's nid.
427  *
428  * The ofs_in_node is used by only data page. It represents offset
429  * from node's page's beginning to get a data block address.
430  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
431  */
432 #define ENTRIES_IN_SUM		512
433 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
434 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
435 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
436 
437 /* a summary entry for a 4KB-sized block in a segment */
438 struct f2fs_summary {
439 	__le32 nid;		/* parent node id */
440 	union {
441 		__u8 reserved[3];
442 		struct {
443 			__u8 version;		/* node version number */
444 			__le16 ofs_in_node;	/* block index in parent node */
445 		} __packed;
446 	};
447 } __packed;
448 
449 /* summary block type, node or data, is stored to the summary_footer */
450 #define SUM_TYPE_NODE		(1)
451 #define SUM_TYPE_DATA		(0)
452 
453 struct summary_footer {
454 	unsigned char entry_type;	/* SUM_TYPE_XXX */
455 	__le32 check_sum;		/* summary checksum */
456 } __packed;
457 
458 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
459 				SUM_ENTRY_SIZE)
460 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
461 				sizeof(struct nat_journal_entry))
462 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
463 				sizeof(struct nat_journal_entry))
464 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
465 				sizeof(struct sit_journal_entry))
466 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
467 				sizeof(struct sit_journal_entry))
468 
469 /* Reserved area should make size of f2fs_extra_info equals to
470  * that of nat_journal and sit_journal.
471  */
472 #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
473 
474 /*
475  * frequently updated NAT/SIT entries can be stored in the spare area in
476  * summary blocks
477  */
478 enum {
479 	NAT_JOURNAL = 0,
480 	SIT_JOURNAL
481 };
482 
483 struct nat_journal_entry {
484 	__le32 nid;
485 	struct f2fs_nat_entry ne;
486 } __packed;
487 
488 struct nat_journal {
489 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
490 	__u8 reserved[NAT_JOURNAL_RESERVED];
491 } __packed;
492 
493 struct sit_journal_entry {
494 	__le32 segno;
495 	struct f2fs_sit_entry se;
496 } __packed;
497 
498 struct sit_journal {
499 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
500 	__u8 reserved[SIT_JOURNAL_RESERVED];
501 } __packed;
502 
503 struct f2fs_extra_info {
504 	__le64 kbytes_written;
505 	__u8 reserved[EXTRA_INFO_RESERVED];
506 } __packed;
507 
508 struct f2fs_journal {
509 	union {
510 		__le16 n_nats;
511 		__le16 n_sits;
512 	};
513 	/* spare area is used by NAT or SIT journals or extra info */
514 	union {
515 		struct nat_journal nat_j;
516 		struct sit_journal sit_j;
517 		struct f2fs_extra_info info;
518 	};
519 } __packed;
520 
521 /* 4KB-sized summary block structure */
522 struct f2fs_summary_block {
523 	struct f2fs_summary entries[ENTRIES_IN_SUM];
524 	struct f2fs_journal journal;
525 	struct summary_footer footer;
526 } __packed;
527 
528 /*
529  * For directory operations
530  */
531 #define F2FS_DOT_HASH		0
532 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
533 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
534 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
535 
536 typedef __le32	f2fs_hash_t;
537 
538 /* One directory entry slot covers 8bytes-long file name */
539 #define F2FS_SLOT_LEN		8
540 #define F2FS_SLOT_LEN_BITS	3
541 
542 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
543 
544 /* MAX level for dir lookup */
545 #define MAX_DIR_HASH_DEPTH	63
546 
547 /* MAX buckets in one level of dir */
548 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
549 
550 /*
551  * space utilization of regular dentry and inline dentry (w/o extra reservation)
552  *		regular dentry		inline dentry (def)	inline dentry (min)
553  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
554  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
555  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
556  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
557  * total	4096			3488			40
558  *
559  * Note: there are more reserved space in inline dentry than in regular
560  * dentry, when converting inline dentry we should handle this carefully.
561  */
562 #define NR_DENTRY_IN_BLOCK	214	/* the number of dentry in a block */
563 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
564 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
565 					BITS_PER_BYTE)
566 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
567 				F2FS_SLOT_LEN) * \
568 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
569 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
570 
571 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
572 struct f2fs_dir_entry {
573 	__le32 hash_code;	/* hash code of file name */
574 	__le32 ino;		/* inode number */
575 	__le16 name_len;	/* length of file name */
576 	__u8 file_type;		/* file type */
577 } __packed;
578 
579 /* 4KB-sized directory entry block */
580 struct f2fs_dentry_block {
581 	/* validity bitmap for directory entries in each block */
582 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
583 	__u8 reserved[SIZE_OF_RESERVED];
584 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
585 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
586 } __packed;
587 
588 /* file types used in inode_info->flags */
589 enum {
590 	F2FS_FT_UNKNOWN,
591 	F2FS_FT_REG_FILE,
592 	F2FS_FT_DIR,
593 	F2FS_FT_CHRDEV,
594 	F2FS_FT_BLKDEV,
595 	F2FS_FT_FIFO,
596 	F2FS_FT_SOCK,
597 	F2FS_FT_SYMLINK,
598 	F2FS_FT_MAX
599 };
600 
601 #define S_SHIFT 12
602 
603 #define	F2FS_DEF_PROJID		0	/* default project ID */
604 
605 #endif  /* _LINUX_F2FS_FS_H */
606